overcoming resentment

Which materials and or classes do you recommend I watch and read to best learn how to get past resentment? I don’t mean a little resentment, or light resentment, I mean defcon level 1 resentment! It is overflowing and shutting me down. It is in response to behaviors by some around me that continue in spite of counseling, talking, begging and pleading so it doesn’t seem to be anything I can leave in the past as it continues and continues to impact me by default. Any tools that are specific to this that you can recommend would be greatly appreciated.